1. Field of the Invention
The present invention relates to an electrophotographic image forming apparatus which forms an electrostatic latent image on an electrophotographic photosensitive member by an electrophotographic method and visualize the electrostatic latent image by developer contained in a developing device, a developing device and a process cartridge.
Here, the electrophotographic image forming apparatus includes, for example, an electrophotographic copying machine, an electrophotographic printer (e.g., an LED printer, a laser beam printer), an electrophotographic facsimile machine and an electrophotographic word processor.
In addition, the process cartridge is a cartridge in which at least one of charging means, developing means and cleaning means and an electrophotographic photosensitive member are integrally incorporated and which is detachably mountable on an electrophotographic image forming apparatus main body, or a cartridge in which at least developing means and an electrophotographic photosensitive member are integrally incorporated and which is detachably mountable on an electrophotographic image forming apparatus main body.
2. Related Background Art
Conventionally, in an electrophotographic image forming apparatus using an electrophotographic image forming process, a process-cartridge method is widely employed with which an electrophotographic photosensitive member and processing means acting on the electrophotographic photosensitive member are integrally incorporated in a cartridge, which is made detachably mountable on an electrophotographic image forming apparatus main body.
In such a process cartridge method, operability can be remarkably improved because an apparatus can be maintained by a user in person rather than by a repairer.
In addition, in an electrophotographic image forming apparatus of such a process cartridge method, a user replaces the cartridge in person. Thus, some apparatuses are provided with toner amount detecting means in order to let a user notice that only a little developer (toner) remains. As the toner amount detecting means, there is a method of detecting a toner amount by detecting a change of capacitance between two electrodes disposed in a process cartridge.
As a configuration of such electrodes, a conductive member is disposed a predetermined distance apart from a developer bearing member (for detecting capacitance between the conductive member and a developing roller).
The present invention has been devised by further developing the above-mentioned conventional art.
It is an object of the present invention to provide a developing device and a process cartridge which prevent developer from leaking outside, an electrophotographic image forming apparatus using the developing device, and an electrophotographic image forming apparatus on which the process cartridge is detachably mountable.
It is another object of the present invention to provide a developing device and a process cartridge which can be easily assembled, an electrophotographic image forming apparatus using the developing device, and an electrophotographic image forming apparatus on which the process cartridge is detachably mountable.
It is yet another object of the present invention to provide a developing device and a process cartridge which is capable of securely making electrical connection with an apparatus main body, an electrophotographic image forming apparatus using the developing device, and an electrophotographic image forming apparatus on which the process cartridge is detachably mountable.
It is yet another object of the present invention to provide a developing device, a process cartridge and an electrophotographic image forming apparatus which can be easily assembled and are capable of certainly preventing the occurrence of developer leakage and securely making electrical connection with the inside and the outside of a developing container.
It is yet another object of the present invention to provide a developing device that comprises a developing container; an electrode to be mounted inside the developing container; a conductive member for securing electric conduction from the inside to the outside of the developing container, wherein the conductive member and the electrode are electrically connected by the conductive member being pressed into a fitting portion provided in the electrode; and an elastic seal member pressed into an interval between the conductive member and the developing container, a process cartridge having the developing device, an electrophotographic image forming apparatus using the developing device and an electrophotographic image forming apparatus on which the process cartridge is detachably mountable.